A couple of quick questions

[Sphinx]

Hi guys, I've been doing a bit more welding lately and I've come accross a couple of things I'd like to question you more experienced welders about.

Using the thin metal technique, or any other 'pulse' type system for that matter I found that the wire was sticking to the weld pool, not badly but just enough to have to 'zap' it for a fraction of a second to get it off. So I couldn't pulse, then move, then pulse. Is this a wire feed issue?

One other thing, has anyone else experienced problems with seem sealer in panels affecting welds? I was butt welding a plate in on a car panel, all good steel but close to the edge where the original skin was folded over. When I went to weld, the heat would cause the sealer to melt and almost explode making the weld spatter all over the place.
I'm not talking about a bit blob of sealer either, just the small amount that is left between the surfaces right inside the fold. I know there's no 'solution' to this, just wondered if anyone else has ever experienced this?

Thanks

 

[Mad Mick]

Hi,check your burn back control,i.e.alter length of time arc continues after wire feed stops.Also keep your torch as close to the work piece as possible.As for your explosive issue,I guess it must be combustible products emanating from your sealer invading your shielding gas,hope this helps,Mick

 

[Sphinx]

Thanks Mick. I'm not sure how to check the burn back, is that a setting on the welder? all it's got it power and wire speed (wire speed goes up automatically with power).

 

[Mad Mick]

Hi again,if no burn back control,suggest you turn down your wire speed a gnat's wotsit or up your volts a gnat's,hope this helps,regards,Mick

 

[Mad Mick]

Hi again,if no burn back control,suggest you turn down your wire speed a gnat's wotsit or up your volts a gnat's,hope this helps,regards,Mick

 

[Sparkey]

Lollol! i think he got it the first time Mick!
What's a gnat's wotsit??

 

[Sphinx]

Thanks Mick.

Thanks Mick.

(see what I did there?.....I crack myself up...)

The wire speed would explain it as when I was setting it up I increased the speed and then found the wire feed was slipping a bit, I probably didn't lower it quite enough before I started.
As for the seam sealer, it was a real pain in the **** as one side went well but the other was a few mm wider and therefore into the edge a bit more and it spattered like a b*****d; I was welding plates in a bootlid where the spoiler holes used to be. The only other time I've experienced this is when I was welding the edge of a bonnet, again where the skin was folded over.

Oh! One more question:
What would cause a white(ish) powder type substance on the reverse side of a weld?

 

[Mad Mick]

I guess zinc plate,avoid the fumes,not healthy.Incidentally a gnat's cock is a universally recognised engineering measurement of approx. 5 thou",only exceeded by a midge's dick which varies from between 1 lightwave & 4.999999 thou",Regards,Mick

 

[Sparkey]

I guess zinc plate,avoid the fumes,not healthy.Incidentally a gnat's cock is a universally recognised engineering measurement of approx. 5 thou",only exceeded by a midge's dick which varies from between 1 lightwave & 4.999999 thou",Regards,Mick

LOL